The presence of γδ T cell receptor (TCR)-expressing cells in the epidermis of mice, termed dendritic epidermal T cells (DETCs), is well established. Because of their strict epidermal localization, it is likely that DETCs primarily respond to epithelial stress, such as infections or the presence of transformed cells, whereas they may not participate directly in dermal immune responses. In this study, we describe a prominent population of resident dermal γδ T cells, which differ from DETCs in TCR usage, phenotype, and migratory behavior. Dermal γδ T cells are radioresistant, cycle in situ, and are partially depend on <em>interleukin</em> (IL)-7, but not IL-<em>15</em>, for their development and survival. During mycobacterial infection, dermal γδ T cells are the predominant dermal cells that produce IL-17. Absence of dermal γδ T cells is associated with decreased expansion in skin draining lymph nodes of CD4(+) T cells specific for an immunodominant Mycobacterium tuberculosis epitope. Decreased CD4(+) T cell expansion is related to a reduction in neutrophil recruitment to the skin and decreased BCG shuttling to draining lymph nodes. Thus, dermal γδ T cells are an important part of the resident cutaneous immunosurveillance program. Our data demonstrate functional specialization of T cells in distinct microcompartments of the skin.

OBJECTIVE

To update response duration and survival data for patients with metastatic renal cell carcinoma treated with high-dose interleukin (IL)-2.

METHODS

Two hundred fifty-five assessable patients were entered onto seven phase II clinical trials. Recombinant IL-2 600,000 or 720,000 IU/kg was administered by 15-minute intravenous infusion every 8 hours for up to 14 consecutive doses over 5 days as clinically tolerated with maximal support. A second, identical cycle of treatment was scheduled following 5 to 9 days of rest, and courses could be repeated every 6 to 12 weeks in stable or responding patients. All data were updated as of December 1998, with report forms completed by the clinical investigators. These data had last been updated as part of the Food and Drug Administration reporting requirements in 1996.

RESULTS

Objective responses previously have been reported in 37 of 255 patients (15%) with 17 complete responses (7%) and 20 partial responses (8%). These data remain unchanged from previous reports. Median response duration for all objective responders remains unchanged at 54 months, but the range now extends from 3 to>> 131 months. Median duration for all complete responses has not yet been reached, but was at least 80 months (range, 7->> 131 mo) at the time of this analysis. Median duration for all partial responses remains 20 months (range, 3->> 126 mo). Median survival time for all 255 patients remains 16.3 months, with 10% to 20% of patients estimated to be alive 5 to 10 years after treatment with high-dose IL-2.

CONCLUSIONS

With prolonged follow-up, treatment with high-dose recombinant IL-2 remains extremely effective for a subset of patients with metastatic renal cell carcinoma.

The complexity of the events of embryo implantation and placentation is exemplified by the number and range of cytokines with demonstrated roles in these processes. Disturbance of the normal expression or action of these cytokines results in complete or partial failure of implantation and abnormal placental formation in mice or humans. Of known importance are members of the gp130 family such as <em>interleukin</em>-11 (IL-11) and leukaemia inhibitory factor (LIF), the transforming growth factor beta (TGFbeta) superfamily including the activins, the colony-stimulating factors (CSF), the IL-1 system and IL-<em>15</em> system. New data are also emerging for roles for a number of chemokines (chemoattractive cytokines) both in recruiting specific cohorts of leukocytes to implantation sites and in trophoblast differentiation and trafficking. This review focuses on those cytokines and chemokines whose expression pattern in the human endometrium is consistent with a potential role in implantation and placentation and for which some relevant actions are known. It examines what is known of their regulation and action along with alterations in clinically relevant situations.

Resting lymphocyte survival is dependent upon the expression of Bcl-2, yet the factors responsible for maintaining lymphocyte Bcl-2 protein expression in vivo are largely unknown. Natural killer (NK) cells are bone marrow-derived lymphocytes that constitutively express the beta and common gamma(c) subunits of the IL-2 receptor (R) as a heterodimer with intermediate affinity for IL-2. IL-<em>15</em> also binds to IL-2Rbeta gamma(c) and is much more abundant in normal tissues than IL-2. Mice that lack the IL-2 gene have NK cells, whereas mice and humans that lack IL-2R gamma(c) do not have NK cells. Further, treatment of mice with an antibody directed against IL-2Rbeta results in a loss of the NK cell compartment. These data suggest that a cytokine other than IL-2, which binds to IL-2Rbeta gamma(c), is important for NK cell development and survival in vivo. In the current report, we show that the recently described IL-<em>15</em>R(alpha) subunit cooperates with IL-2Rbeta gamma(c) to transduce an intracellular signal at picomolar concentrations of IL-<em>15</em>. We demonstrate that resting human NK cells express IL-<em>15</em>R(alpha) mRNA and further, that picomolar amounts of IL-<em>15</em> can sustain NK cell survival for up to 8 d in the absence of serum. NK cell survival was not sustained by other monocyte-derived factors (i.e., TNF-alpha, IL-1beta, IL-10, IL-12) nor by cytokines known to use gamma(c) for signaling (i.e., IL-4, IL-7, IL-9, IL- 13). One mechanism by which IL-<em>15</em> promotes NK cell survival may involve the maintenance of Bcl-2 protein expression. Considering these functional properties of IL-<em>15</em> and the fact that it is produced by bone marrow stromal cells and activated monocytes, we propose that IL-<em>15</em> may function as an NK cell survival factor in vivo.

Hyperosmolarity has been recognized to be a pro-inflammatory stress to the corneal epithelium. The cell signalling pathways linking hyperosmolar stress and inflammation have not been well elucidated. This study investigated whether exposure of human limbal epithelial cells to hyperosmotic stress activates the mitogen-activated protein kinase (MAPK) pathways and induces production of pro-inflammatory cytokines, <em>interleukin</em> (IL) -1beta, tumor necrosis factor (TNF) alpha, and the C-X-C chemokine IL-8. Primary human limbal epithelial cultures in normal osmolar media (312 mOsM) were exposed to media with higher osmolarity (400-500 mOsM) by adding 50-90 mM NaCl, with or without SB202190, an inhibitor of c-Jun N-terminal kinases (JNK) pathway, PD 98059, an inhibitor of extracellular-regulated kinase (ERK) pathway, dexamethasone or doxycycline for different lengths of time. The conditioned media were collected after 24 hr of treatment for ELISA. Total RNA was extracted from cultures treated for 6 hr for semi-quantitative RT-PCR. Cells treated for <em>15</em>-60 min were lysed in RIPA buffer and subjected to Western blot with phospho (p)-specific antibodies against p-JNK and p-ERK. The concentrations of IL-1beta, TNF-alpha and IL-8 proteins in 24 hr conditioned media of limbal epithelial cells progressively increased as the media osmolarity increased from 312 to 500 mOsM. Active p-JNK-1/p-JNK-2 and p-ERK-1/p-ERK-2 were detected by Western blot and peaked at 60 min in cells exposed to hyperosmolar media. The levels of p-JNK-1/p-JNK-2 and p-ERK1/p-ERK2 were positively correlated with the medium osmolarity. SB202190, PD98059 and doxycycline markedly suppressed the levels of p-JNK-1/p-JNK-2 and/or p-ERK1/p-ERK2, as well as IL-1beta, TNF-alpha and IL-8 mRNAs and proteins stimulated by hyperosmolar media. These findings provide direct evidence that hyperosmolarity induces inflammation in human limbal epithelial cells by increasing expression and production of pro-inflammatory cytokines and chemokines, a process that appears to be mediated through activation of the JNK and ERK MAPK signalling pathways. The efficacy of doxycycline in treating ocular surface diseases may be due to its ability to suppress JNK and ERK signalling activation and inflammatory mediator production in the limbal epithelium.

Importance: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can be documented in various tissues, but the frequency of cardiac involvement as well as possible consequences are unknown.

Objective: To evaluate the presence of SARS-CoV-2 in the myocardial tissue from autopsy cases and to document a possible cardiac response to that infection.

Design, setting, and participants: This cohort study used data from consecutive autopsy cases from Germany between April 8 and April 18, 2020. All patients had tested positive for SARS-CoV-2 in pharyngeal swab tests.

Exposures: Patients who died of coronavirus disease 2019.

Main outcomes and measures: Incidence of SARS-CoV-2 positivity in cardiac tissue as well as CD3+, CD45+, and CD68+ cells in the myocardium and gene expression of tumor necrosis growth factor α, interferon γ, chemokine ligand 5, as well as interleukin-6, -8, and -18.

Results: Cardiac tissue from 39 consecutive autopsy cases were included. The median (interquartile range) age of patients was 85 (78-89) years, and 23 (59.0%) were women. SARS-CoV-2 could be documented in 24 of 39 patients (61.5%). Viral load above 1000 copies per μg RNA could be documented in 16 of 39 patients (41.0%). A cytokine response panel consisting of 6 proinflammatory genes was increased in those 16 patients compared with 15 patients without any SARS-CoV-2 in the heart. Comparison of 15 patients without cardiac infection with 16 patients with more than 1000 copies revealed no inflammatory cell infiltrates or differences in leukocyte numbers per high power field.

Conclusions and relevance: In this analysis of autopsy cases, viral presence within the myocardium could be documented. While a response to this infection could be reported in cases with higher virus load vs no virus infection, this was not associated with an influx of inflammatory cells. Future investigations should focus on evaluating the long-term consequences of this cardiac involvement.

Serum concentrations of immunoreactive tumor necrosis factor/cachectin (TNF), <em>interleukin</em>-1 beta (IL-1 beta), interferon-gamma (IFN gamma), and interferon-alpha (IFN alpha) were prospectively measured in 70 patients with septic shock to determine their evolution and prognostic values. In a univariate analysis, levels of TNF (P = .002) and IL-1 beta (P = .05) were associated with the patient's outcome, but not IFN alpha (P = .<em>15</em>) and IFN gamma (P = .26). In contrast, in a stepwise logistic regression analysis, the severity of the underlying disease (P = .01), the age of the patient (P = .02), the documentation of infection (nonbacteremic infections vs. bacteremias, P = .03), the urine output (P = .04), and the arterial pH (P = .05) contributed more significantly to prediction of patient outcome than the serum levels of TNF (P = .07). After 10 days, the median concentration of TNF was undetectable (less than 100 pg/ml) in the survivors, whereas it remained elevated (305 pg/ml, P = .002) in the nonsurvivors. Thus, in patients with septic shock due to various gram-negative bacteria, other parameters than the absolute serum concentration of immunoreactive TNF contributed significantly to the prediction of outcome.

BACKGROUND

The effect of individual dietary fatty acids on emerging risk factors for cardiovascular disease that are associated with subclinical inflammation is unknown.

OBJECTIVE

The goal was to evaluate the role of dietary fat and specific fatty acids, especially trans fatty acids, in altering concentrations of markers of inflammation in humans fed controlled diets.

METHODS

In a randomized crossover design, 50 men consumed controlled diets for 5 wk that provided <em>15</em>% of energy from protein, 39% of energy from fat, and 46% of energy from carbohydrate. Eight percent of fat or fatty acids was replaced across diets with the following: cholesterol, oleic acid, trans fatty acids (TFAs), stearic acid (STE), TFA+STE (4% of energy each), and 12:0-16:0 saturated fatty acids (LMP).

RESULTS

Fibrinogen concentrations were higher after consumption of the diet enriched in stearic acid than after consumption of the carbohydrate diet. C-reactive protein concentrations were higher after consumption of the TFA diet than after consumption of the carbohydrate diet, but were not significantly different after consumption of the TFA and TFA+STE diets than after consumption of the LMP diet. Interleukin 6 concentrations were lower after consumption of the oleic acid diet than after consumption of the LMP, TFA, and STE diets. E-selectin concentrations were higher after consumption of the TFA diet than after consumption of the carbohydrate diet. Consumption of the TFA but not the TFA+STE diet resulted in higher E-selectin concentrations than did the LMP diet.

CONCLUSIONS

These data provide evidence that dietary fatty acids can modulate markers of inflammation. Although stearic acid minimally affects LDL cholesterol, it does appear to increase fibrinogen concentrations.

We have applied immunohistology and in situ hybridization to bronchial biopsies of patients with chronic obstructive pulmonary disease (COPD) to examine neutrophil recruitment and to determine neutrophil chemoattractant and CXC receptor (CXCR) 1 and CXCR2 gene expression associated with acute severe exacerbations. Cells were counted in endobronchial biopsies of (1) patients with COPD intubated for exacerbations (E-COPD; n = <em>15</em>), (2) those with COPD in a stable phase of their disease (S-COPD; n = 7), and (3) nonsmoker surgical control subjects intubated for a nonrespiratory surgical procedure (n = <em>15</em>). In comparison with the nonrespiratory surgical procedure and S-COPD groups, neutrophilia and gene expression for epithelial-derived neutrophil attractant-78 (CXCL5), <em>interleukin</em>-8 (CXCL8), CXCR1, and CXCR2 were each upregulated in the E-COPD group (p < 0.01); compared with the S-COPD group, by 97-, 6-, 6-, 3-, and 7-fold, respectively (p < 0.01). In E-COPD, there was a significant positive association between the number of neutrophils and CXCR2 mRNA-positive cells (r = 0.79; p < 0.01) but not between the number of neutrophils and CXCR1 mRNA-positive cells. At the time of sampling of the mucosa, there was no association between neutrophil number and either the length of intubation or viral infection. Thus, in COPD, in addition to CXCL8 and CXCR1, CXCL5 and CXCR2 appear to play important roles in the airway neutrophilia characteristic of severe exacerbations.

Regulation of immune system is of paramount importance to prevent immune attacks against self-components. Mice deficient in the <em>interleukin</em> (IL)-2/IL-<em>15</em> receptor beta chain, CD122, are model animals of such immune attacks and characteristically have a high number of abnormally activated T cells. Here, we show that the transfer of CD8+CD122+ cells into CD122-deficient neonates totally prevented the development of abnormal T cells. Furthermore, recombination activating gene-2-/- mice that received wild-type mice-derived CD8+CD122- cells died within 10 wk after cell transfer, indicating that normal CD8+CD122- cells become dangerously activated T cells in the absence of CD8+CD122+ T cells. CD8+CD122+ cells could control activated CD8+ or CD4+ T cells both in vivo and in vitro. Our results indicate that the CD8+CD122+ population includes naturally occurring CD8+ regulatory T cells that control potentially dangerous T cells.

<em>Interleukin</em>-6 (IL-6) synthesized in response to diverse stimuli may play an important role in bridging the inflammatory and atherosclerotic processes. The acute-phase response after coronary artery bypass graft surgery (CABG) is associated with the induction and release of cytokines, such as IL-6. We have examined the effect of common polymorphisms in the IL-6 gene promoter (-174G>C, -572G>C, and -597G>A) on IL-6 levels after elective CABG. DNA extracted from the peripheral blood of 127 patients was amplified by polymerase chain reaction. IL-6 genotypes were resolved by gel electrophoresis after restriction enzyme digestion. Serum IL-6 was measured before surgery and in serial samples at 6, 24, 48, and 72 hours after CABG. Genotype distribution was as expected for a population in Hardy-Weinberg equilibrium for all polymorphisms. Rare allele frequencies (+/-95% CIs) were similar to those reported previously: -597A 0.36 (0.30 to 0.42), -572C 0.07 (0.04 to 0.10), and -174C 0.37 (0.31 to 0.43). The -174G>C and -597G>A genotypes were in strong allelic association (Delta=0.97, P<0.001). Baseline IL-6 levels did not significantly differ between patients with different genotypes for any polymorphism. However, 6 hours after CABG, peak IL-6 levels were significantly higher (P=0.03) in carriers of the -572C allele than in those of the -572GG genotype (355+/-67 versus 216+/-13 pg/mL, respectively) and in those with genotype -174CC compared with -174G allele carriers (287+/-31 versus 227+/-<em>15</em> pg/mL, respectively; P=0.04). These effects remained statistically significant after adjusting for possible confounders, including age, sex, smoking, duration of cardiopulmonary bypass, aortic cross-clamp time, and total duration of surgery. These data demonstrate that IL-6 promoter polymorphisms influence peak IL-6 production after CABG, suggesting that these polymorphisms, which are functional in vitro, are also functional in vivo, suggesting a genetic influence on IL-6 levels after acute severe injury.

Changes in T-cell function are a hallmark of human immunodeficiency virus type 1 (HIV-1) infection, but the pathogenic mechanisms leading to these changes are unclear. We examined the gene expression profiles in ex vivo human CD4+ and CD8+ T cells from untreated HIV-1-infected individuals at different clinical stages and rates of disease progression. Profiles of pure CD4+ and CD8+ T-cell subsets from HIV-1-infected nonprogressors with controlled viremia were indistinguishable from those of individuals not infected with HIV-1. Similarly, no gene clusters could distinguish T cells from individuals with early infection from those seen in chronic progressive HIV-1 infection, whereas differences were observed between uninfected individuals or nonprogressors versus early or chronic progressors. In early and chronic HIV-1 infection, three characteristic gene expression signatures were observed. (i) CD4+ and CD8+ T cells showed increased expression of interferon-stimulated genes (ISGs). However, some ISGs, including CXCL9, CXCL10, and CXCL11, and the <em>interleukin</em>-<em>15</em> alpha receptor were not upregulated. (ii) CD4+ and CD8+ T cells showed a cluster similar to that observed in thymocytes. (iii) More genes were differentially regulated in CD8+ T cells than in CD4+ T cells, including a cluster of genes downregulated exclusively in CD8+ T cells. In conclusion, HIV-1 infection induces a persistent T-cell transcriptional profile, early in infection, characterized by a dramatic but potentially aberrant interferon response and a profile suggesting an active thymic output. These findings highlight the complexity of the host-virus relationship in HIV-1 infection.

Epithelial cells may form the first barrier of defense against bacteria in human tissues. We recently revealed that oral epithelial cells generated anti-bacterial factors, such as peptidoglycan recognition proteins (PGRPs) and beta-defensin 2, but not proinflammatory cytokines, such as <em>interleukin</em>-8 (IL-8), upon stimulation with bacterial cell-surface components. In this study, we found clear expressions of Toll-like receptor (TLR)2, TLR3, TLR4, TLR7, NOD1 and NOD2 in oral, tongue, salivary gland, pharyngeal, esophageal, intestinal, cervical, breast, lung, and kidney epithelial cells. However, tongue, salivary gland, pharyngeal, esophageal, intestinal, cervical, breast, lung, and kidney epithelial cells, as well as oral epithelial cells, did not secrete IL-6, IL-8 or monocyte chemoattractant protein-1 in response to chemically synthesized TLR and NOD agonists mimicking microbial components: TLR2 agonistic lipopeptide (Pam3CSSNA), TLR3 agonistic Poly I:C, TLR4 agonistic lipid A (LA-<em>15</em>-PP), TLR7 agonistic single stranded RNA (ssPoly U), NOD1 agonistic iE-DAP (gamma-D-glumtamyl-meso-diaminopimelic acid), and NOD2 agonistic muramyldipeptide (MDP). Although PGRPs on oral epithelial cells were significantly up-regulated upon stimulation with these synthetic components, PGRPs on pharyngeal epithelial cells were only slightly up-regulated, and PGRPs on esophageal, intestinal and cervical epithelial cells were not up-regulated upon stimulation with the components. In contrast, stimulation with synthetic TLRs and NODs ligands induced beta-defensin 2 generation in all epithelial cells examined. These findings indicate that TLR and NOD in various epithelial cells are functional receptors that induce anti-bacterial responses in general without being accompanied by inflammatory responses.

Cytokines have been implicated as immunological effector molecules that mediate beta cell destruction associated with insulin-dependent diabetes mellitus. In this report we demonstrate that the cytokine combination of human recombinant <em>interleukin</em> 1 beta (IL-1 beta), tumor necrosis factor alpha (TNF-alpha), and interferon gamma (IFN-gamma) induces the formation of nitric oxide by human islets. This combination of cytokines stimulates both the formation of the nitric oxide derivative, nitrite, and the accumulation of cGMP by human islets. The nitric oxide synthase inhibitor NG-monomethyl-L-arginine prevents formation of both cGMP and nitrite. IL-1 beta and IFN-gamma are sufficient to induce nitric oxide formation by human islets, whereas TNF-alpha potentiates nitrite production. This combination of cytokines (IL-1 beta, TNF-alpha, and IFN-gamma) also influences insulin secretion by human islets. Pretreatment of human islets with low concentrations of this cytokine combination (IL-1 beta at <em>15</em> units/ml, 0.7 nM TNF-alpha, and IFN-gamma at <em>15</em>0 units/ml) appears to slightly stimulate insulin secretion. Higher concentrations (IL-1 beta at 75 units/ml, 3.5 nM TNF-alpha, and IFN-gamma at 750 units/ml) inhibit insulin secretion from human islets, and the inhibitory effect is prevented by NG-monomethyl-L-arginine. This higher concentration of cytokines also induces the formation of an electron paramagnetic resonance-detectable g = 2.04 axial feature by human islets that is characteristic of the formation of an iron-dithio-dinitrosyl complex. The formation of this complex is prevented by NG-monomethyl-L-arginine, thus confirming that this cytokine combination induces the formation of nitric oxide by human islets. These results indicate that nitric oxide mediates the inhibitory effects of cytokines on glucose-stimulated insulin secretion by human islets and suggest that nitric oxide may participate in beta-cell dysfunction associated with insulin-dependent diabetes mellitus.

The Tec family tyrosine kinases, Itk and Rlk, are expressed in thymocytes and peripheral T cells and regulate thresholds of T cell receptor signaling. Yet little is known about the specific role of Itk- and Rlk-dependent signals in CD8(+) T cell maturation. We show here that Itk(-/-) and Rlk(-/-)Itk(-/-) mice were nearly devoid of conventional CD8(+) T cells and, instead, contained a large population of CD8(+) T cells that bear striking similarity to lineages of innate lymphocytes. Itk(-/-) and Rlk(-/-)Itk(-/-) CD8(+) thymocytes and T cells were CD44(hi), CD122(+), and NK1.1(+); were able to produce interferon-gamma directly ex vivo; and were dependent on <em>interleukin</em>-<em>15</em>. Itk(-/-) and Rlk(-/-)Itk(-/-) CD8(+) thymocytes expressed abundant transcripts for the T box transcription factor, eomesodermin, correlating with their phenotype and function. These data indicate a critical role for Itk and Rlk in conventional CD8(+) T cell development in the thymus.

The formation of memory CD8 T cells is an important goal of vaccination. However, although widespread use of booster immunizations in humans generates secondary and tertiary CD8 T cell memory, experimental data are limited to primary CD8 T cell memory. Here, we show that, compared with primary memory CD8 T cells, secondary memory CD8 T cells exhibit substantially delayed conversion to a central-memory phenotype, as determined by CD62L expression and <em>interleukin</em> (IL)-2 production. This delayed conversion to a central-memory phenotype correlates with reduced basal proliferation and responsiveness to IL-<em>15</em>, although in vitro coculture with a high concentration of IL-<em>15</em> is capable of inducing proliferation and CD62L upregulation. Functionally, secondary memory CD8 T cells are more protective in vivo on a per cell basis, and this may be explained by sustained lytic ability. Additionally, secondary memory CD8 T cells are more permissive than primary memory CD8 T cells for new T cell priming in lymph nodes, possibly suggesting a mechanism of replacement for memory T cells. Thus, primary and secondary memory CD8 T cells are functionally distinct, and the number of encounters with antigen influences memory CD8 T cell function.

OBJECTIVE

We assessed the relationships between four circulating acute phase proteins and the circulating and adipose tissue levels of three adipocytokines.

METHODS

In all, <em>15</em> nondiabetic obese women with a body mass index (BMI) above 32 kg/m(2) were investigated.

METHODS

Circulating concentrations of C-reactive protein (CRP), alpha 1 acid glycoprotein (AAG), fibrinogen, alpha 1 antitrypsin and both circulating and adipose tissue levels of interleukin (IL)-6, tumor necrosis factor (TNF)alpha and leptin were measured by either nephelometry or enzyme-linked immunosorbent assay.

RESULTS

We found a strong positive correlation between both circulating and adipose tissue levels of IL-6, TNFalpha and leptin and serum CRP levels. All these adipose tissue adipocytokines were also positively correlated with serum AAG levels. These correlations disappeared when adjusted for fat mass, suggesting that the relationship observed was dependent on fat amount.

CONCLUSIONS

Our results indicate a strong relationship between adipocytokines and inflammatory markers, and suggest that cytokines secreted by adipose tissue in obese subjects could play a role in increased inflammatory proteins secretion by the liver.

BACKGROUND

Immunoreactivity for several chemokines and for their related receptors has been demonstrated in resident cells of the central nervous system, and the up-regulation of some of them is associated with pathological changes found in Alzheimer disease (AD).

OBJECTIVE

To determine interferon-gamma-inducible protein 10 (IP-10), monocyte chemotactic protein 1 (MCP-1), and interleukin 8 (IL-8) levels in cerebrospinal fluid (CSF) from subjects with amnestic mild cognitive impairment (MCI) and patients with AD as compared with age-matched controls.

METHODS

Thirty-eight subjects with amnestic MCI, 36 patients with AD, and 41 age-matched subjects with noninflammatory affections of the nervous system.

METHODS

Evaluation of CSF chemokine production at time of diagnosis of MCI and AD; correlation with clinical and personal data. Longitudinal evaluation of subjects with MCI until conversion to AD.

RESULTS

Cerebrospinal fluid IP-10 concentration was significantly increased in patients with MCI and mild AD but not in patients with severe AD (Mini-Mental State Examination score <15), whereas MCP-1 and IL-8 levels were increased in patients with MCI and all patients with AD. A significant positive correlation between Mini-Mental State Examination score and CSF IP-10 or MCP-1 concentration was observed in patients with AD. No correlation between IP-10 levels and age was found, whereas MCP-1 and IL-8 levels correlated positively with age. Out of 38 subjects with MCI, 19 developed AD within a 1- to 3-year follow-up.

CONCLUSIONS

The presence of inflammatory molecules is likely to be a very early event in AD pathogenesis, even preceding the clinical onset of the disease, as demonstrated by subjects with MCI who developed AD over time. Interferon-gamma-inducible protein 10 is specifically increased in MCI and seems to decrease with the progression of AD, whereas MCP-1 and IL-8 are up-regulated also in late stages of the disease, suggesting a role in phases in which neurodegeneration is prevalent.

Atopic dermatitis is a chronic inflammatory skin disease that affects <em>15</em>-30% of children and approximately 5% of adults in industrialized countries. Although the pathogenesis of atopic dermatitis is not fully understood, the disease is mediated by an abnormal immunoglobulin-E immune response in the setting of skin barrier dysfunction. Mast cells contribute to immunoglobulin-E-mediated allergic disorders including atopic dermatitis. Upon activation, mast cells release their membrane-bound cytosolic granules leading to the release of several molecules that are important in the pathogenesis of atopic dermatitis and host defence. More than 90% of patients with atopic dermatitis are colonized with Staphylococcus aureus in the lesional skin whereas most healthy individuals do not harbour the pathogen. Several staphylococcal exotoxins can act as superantigens and/or antigens in models of atopic dermatitis. However, the role of these staphylococcal exotoxins in disease pathogenesis remains unclear. Here we report that culture supernatants of S. aureus contain potent mast-cell degranulation activity. Biochemical analysis identified δ-toxin as the mast cell degranulation-inducing factor produced by S. aureus. Mast cell degranulation induced by δ-toxin depended on phosphoinositide 3-kinase and calcium (Ca(2+)) influx; however, unlike that mediated by immunoglobulin-E crosslinking, it did not require the spleen tyrosine kinase. In addition, immunoglobulin-E enhanced δ-toxin-induced mast cell degranulation in the absence of antigen. Furthermore, S. aureus isolates recovered from patients with atopic dermatitis produced large amounts of δ-toxin. Skin colonization with S. aureus, but not a mutant deficient in δ-toxin, promoted immunoglobulin-E and <em>interleukin</em>-4 production, as well as inflammatory skin disease. Furthermore, enhancement of immunoglobulin-E production and dermatitis by δ-toxin was abrogated in Kit(W-sh/W-sh) mast-cell-deficient mice and restored by mast cell reconstitution. These studies identify δ-toxin as a potent inducer of mast cell degranulation and suggest a mechanistic link between S. aureus colonization and allergic skin disease.

Coeliac disease is precipitated in susceptible subjects by ingestion of wheat gluten or gluten related prolamins from some other cereals. The disease is strongly associated with certain HLA-DQ heterodimers, for example, DQ2 (DQ alpha 1*0501, beta 1*0201) in most patients and apparently DQ8 (DQ alpha 1*0301, beta 1*0302) in a small subset. Gluten specific T cell clones (TCC) from coeliac intestinal lesions were recently established and found to be mainly restricted by HLA-DQ2 or HLA-DQ8. Antigen induced production of cytokines was studied in <em>15</em> TCC from three patients, 10 being DQ2 and five DQ8 restricted. Cell culture supernatants were prepared by stimulation with gluten peptides in the presence of DQ2+ or DQ8+ Epstein-Barr virus transformed B cells as antigen presenting cells (APC). Supernatants were analysed for cytokines by bioassays, ELISA, and CELISA. Cellular cytokine mRNA was analysed semi-quantitatively by slot blotting and polymerase chain reaction (PCR). All TCC were found to secrete interferon (IFN) gamma, often at high concentrations >> 2000 U/ml); some secreted in addition <em>interleukin</em> (IL) 4, IL 5, IL 6, IL 10, tumour necrosis factor (TNF), and transforming growth factor (TGF) beta. The last TCC thus displayed a Th0-like cytokine pattern. However, other TCC produced IFN gamma and TNF but no IL 4, or IL 5, compatible with a Th1-like pattern. In conclusion, most DQ8 restricted TCC seemed to fit with a Th0 profile whereas the DQ2 restricted TCC secreted cytokines more compatible with a Th1 pattern. The TCC supernatants induced upregulation of HLA-DR and secretory component (poly-Ig receptor) in the colonic adenocarcinoma cell line HT-29.E10, most probably reflecting mainly the high IFN gamma concentrations. This cytokine, particularly in combination with TNF alpha, might be involved in several pathological features of the coeliac lesion. The characterised cytokine profiles thus support the notion that mucosal T cells activated in situ by gluten in a DQ restricted fashion play a central part in the pathogenesis of coeliac disease.

Inflammatory cytokines are released in response to stress, tissue damage, and infection. Acutely, this response is adaptive; however, chronic elevation of inflammatory proteins can contribute to health problems including cardiovascular, endocrine, mood, and sleep disorders. Few studies have examined how sleep deprivation acutely affects inflammatory markers, which was the aim of the current study. Nineteen healthy men and women aged 28.05+/-8.56 (mean+/-SD) were totally sleep deprived for 40 h under constant routine conditions. Pro-inflammatory markers: intracellular adhesion molecule-1 (ICAM-1), E-selectin, vascular adhesion molecule-1 (VCAM-1), c-reactive protein (CRP), <em>interleukin</em>-6 (IL-6), and <em>interleukin</em>-1beta (IL-1beta), and the anti-inflammatory cytokine <em>interleukin</em>-1 receptor antagonist (IL-1ra) were assayed in plasma. Daytime levels during baseline (hours 1-<em>15</em> of scheduled wakefulness) were compared to daytime levels during sleep deprivation (hours 25-39 of scheduled wakefulness), thus controlling for circadian phase within an individual. Repeated measures ANOVA with planned comparisons showed that 40 h of total sleep deprivation induced a significant increase in E-selectin, ICAM-1, IL-1beta, and IL-1ra, a significant decrease in CRP and IL-6, and no significant change in VCAM-1. Alterations in circulating levels of pro- and anti-inflammatory cytokines and cell adhesion molecules during sleep deprivation were consistent with both increased and decreased inflammation. These findings suggest that one night of sleep loss triggers a stress response that includes stimulation of both pro- and anti-inflammatory proteins in the healthy young subjects tested under our experimental conditions.

Survival and intermittent proliferation of memory CD4(+) and CD8(+) T cells appear to be controlled by different homeostatic mechanisms. In particular, contact with <em>interleukin</em> (IL)-<em>15</em> has a decisive influence on memory CD8(+) cells, but not memory CD4(+) cells. Past studies of memory CD4(+) cells have relied heavily on the use of naturally occurring memory phenotype (MP) cells as a surrogate for antigen (Ag)-specific memory cells. However, we show here that MP CD4(+) cells contain a prominent subset of rapidly proliferating major histocompatibility complex (MHC) II-dependent cells. In contrast, Ag-specific memory CD4 cells have a slow turnover rate and are MHC II independent. In irradiated hosts, these latter cells ignore IL-<em>15</em> and expand in response to the elevated levels of IL-7 in the lymphopenic hosts. In contrast, in normal nonlymphopenic hosts where IL-7 levels are low, memory CD4 cells are heavily dependent on IL-<em>15</em>. Significantly, memory CD4(+) responsiveness to endogenous IL-<em>15</em> reflects marked competition from other cells, especially CD8(+) and natural killer cells, and increases considerably after removal of these cells. Therefore, under normal physiological conditions, homeostasis of CD8(+) and CD4(+) memory cells is quite similar and involves IL-<em>15</em> and IL-7.

<em>Interleukins</em> 4 (IL-4) and 13 (IL-13) have been found previously to share receptor components on some cells, as revealed by receptor cross-competition studies. In the present study, the cloning is described of murine NR4, a previously unrecognized receptor identified on the basis of sequence similarity with members of the hemopoietin receptor family. mRNA encoding NR4 was found in a wide range of murine cells and tissues. By using transient expression in COS-7 cells, NR4 was found to encode the IL-13 receptor alpha chain, a low-affinity receptor capable of binding IL-13 but not IL-4 or <em>interleukins</em> 2, -7, -9, or -<em>15</em>. Stable expression of the IL-13 receptor alpha chain (NR4) in CTLL-2 cells resulted in the generation of high-affinity IL-13 receptors capable of transducing a proliferative signal in response to IL-13 and, moreover, led to competitive cross-reactivity in the binding of IL-4 and IL-13. These results suggest that the IL-13 receptor alpha chain (NR4) is the primary binding subunit of the IL-13 receptor and may also be a component of IL-4 receptors.

The aim of this study was to examine the effect of aerobic exercise training on insulin sensitivity in overweight and obese girls. Nineteen overweight and obese girls (mean +/- SD: age, 13.1+/-1.8 years; body mass index, 26.8+/-3.9 kg/m(2)) volunteered for this study. Body composition (dual-energy x-ray absorptiometry), insulin sensitivity (oral glucose tolerance test and homeostasis model assessment estimate of insulin resistance; n=<em>15</em>), adiponectin, C-reactive protein (CRP), <em>interleukin</em> (IL) 6, insulin-like growth factor-1, soluble intercellular adhesion molecule-1 and soluble vascular cell adhesion molecule-1 serum levels, and blood lipids and lipoproteins were assessed before and after 12 weeks of aerobic training. Cardiorespiratory fitness increased by 18.8% (P<.05) as a result of training. The area under the insulin concentration curve (insulin area under the curve) decreased by 23.3% (12781.7+/-7454.2 vs 9799.0+/-4918.6 microU.min/mL before and after intervention, respectively; P=.03). Insulin sensitivity was improved without changes in body weight (pre-intervention, 67.9+/-14.5 kg; post-intervention, 68.3+/-14.0 kg) or percent body fat (pre-intervention, 41.4% +/- 4.8%; post-intervention, 40.7%+/-5.2%). The lower limb fat-free mass increased by 6.2% (P<.01) as a result of training, and changes in lower limb fat-free mass were correlated with changes in the insulin area under the curve (r= -.68; P< .01). Serum adiponectin, IL-6, and CRP concentrations did not change (pre-intervention vs post-intervention: adiponectin, 9.57+/-3.01 vs 9.08+/-2.32 microg/mL; IL-6, 1.67+/-1.29 vs 1.65+/-1.25 pg/mL, CRP, 3.21+/-2.48 vs 2.73+/-1.88 mg/L) whereas insulin-like growth factor-1 was lower after training (pre-intervention, 453.8 +/- <em>15</em>9.3 ng/mL; post-intervention, 403.2+/- <em>15</em>5.1 ng/mL; P<.05). In conclusion, 12 weeks of aerobic training improved insulin sensitivity in overweight and obese girls without change in body weight, percent body fat, and circulating concentrations of adiponectin, IL-6, CRP, and other inflammatory markers. These findings suggest that increased physical activity may ameliorate the metabolic abnormalities associated with obesity in children with a mechanism other than the parameters cited earlier.